Prognostic Meteorological Discussion
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FXUS06 KWBC 181939
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT FRI APRIL 18 2014

6-10 DAY OUTLOOK FOR APR 24 - 28 2014

TODAY`S ENSEMBLE MEAN SOLUTIONS ARE IN FAIR AGREEMENT ON THE 500-HPA FLOW
PATTERN OVER THE FORECAST DOMAIN. HOWEVER, THERE IS LARGE SPREAD AND
UNCERTAINTY AMONG THE COMPONENT ENSEMBLE MEMBERS OVER MUCH OF NORTH AMERICA. A
STRONG JET IS FORECAST OVER THE NORTH PACIFIC CULMINATING WITH A TROUGH NEAR
THE WEST COAST OF THE CONUS. DOWNSTREAM OF THIS TROUGH, LOW-AMPLITUDE FLOW IS
PREDICTED OVER MUCH OF THE CONUS. OVER THE ALASKA SECTOR, A TROUGH IS PREDICTED
FOR THE BERING SEA EXTENDING SOUTHEAST TO THE GULF OF ALASKA. THE DETERMINISTIC
RUNS FROM THE GFS AND ECWMF ARE IN RELATIVELY GOOD AGREEMENT WITH THEIR
RESPECTIVE ENSEMBLE MEAN SOLUTIONS. DUE TO HIGH MODEL SPREAD, TODAY`S OFFICIAL
MANUAL 500-HPA HEIGHT BLEND IS WEIGHTED MOST HEAVILY TOWARD THE ENSEMBLE MEAN
SOLUTIONS.

ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF THE SOUTH-CENTRAL CONUS
DOWNSTREAM OF THE TROUGH PREDICTED OVER THE WEST COAST. ABOVE-NORMAL
TEMPERATURES ARE ALSO FAVORED FOR MUCH OF THE SOUTHEASTERN CONUS UNDERNEATH
LOW-AMPLITUDE FLOW AND WEAKLY POSITIVE 500-HPA HEIGHT ANOMALIES. THE TROUGH
FORECAST OVER THE WEST COAST ENHANCES PROBABILITIES FOR BELOW-NORMAL
TEMPERATURES FOR PARTS OF CALIFORNIA. BELOW-NORMAL TEMPERATURES ARE ALSO
FAVORED FOR PARTS OF THE NORTHERN PLAINS, GREAT LAKES, AND NORTHEAST IN
ASSOCIATION WITH TROUGHS PREDICTED OVER EASTERN CANADA AND OFF THE NEW ENGLAND
COAST, RESPECTIVELY. ABOVE-NORMAL TEMPERATURE PROBABILITIES ARE ENHANCED FOR
MUCH OF ALASKA AHEAD OF A TROUGH AXIS FORECAST OVER THE ALEUTIANS.

ABOVE-MEDIAN PRECIPITATION PROBABILITIES ARE ENHANCED FOR MUCH OF THE WESTERN
CONUS DUE TO A TROUGH FORECAST NEAR THE WEST COAST. ABOVE-MEDIAN PRECIPITATION
IS ALSO FAVORED FOR THE UPPER AND MIDDLE MISSISSIPPI VALLEY, GREAT LAKES AND
NORTHEAST DUE TO THE POTENTIAL FOR SHORTWAVE TROUGHS TO AFFECT THESE REGIONS.
CONVERSELY, THERE ARE INCREASED PROBABILITIES FOR BELOW-MEDIAN PRECIPITATION
FOR PARTS OF THE SOUTHEASTERN CONUS IN ASSOCIATION WITH WEAK RIDGING.
ABOVE-MEDIAN PRECIPITATION IS FAVORED FOR PARTS OF THE ALASKA PANHANDLE AHEAD
OF A TROUGH PREDICTED JUST OFF THE COAST. ENHANCED PROBABILITIES OF
BELOW-MEDIAN PRECIPITATION ARE INDICATED FOR PARTS OF NORTHWESTERN ALASKA TO
THE NORTH OF THE EXPECTED MEAN STORM TRACK.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 5 PERCENT OF TODAY`S OPERATIONAL 0Z
GFS CENTERED ON DAY 8...5 PERCENT OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY
8...10 PERCENT OF TODAY`S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...20 PERCENT
OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...5 PERCENT OF TODAY`S
OPERATIONAL 0Z ECMWF CENTERED ON DAY 8...20 PERCENT OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8...20 PERCENT OF TODAY`S 0Z CANADIAN ENSEMBLE
MEAN CENTERED ON DAY 8...AND 15 PERCENT OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE
MEAN CENTERED ON DAY 7.

MODEL OF THE DAY: NO PREFERENCE

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: BELOW AVERAGE, 2 OUT OF 5, DUE TO
LARGE MODEL SPREAD OVER NORTH AMERICA.

8-14 DAY OUTLOOK FOR APR 26 - MAY 02, 2014

DURING THE WEEK TWO PERIOD, TODAY`S ENSEMBLE MEAN SOLUTIONS CONTINUE TO
FORECAST A FAIRLY STRONG JET OVER THE NORTH PACIFIC WITH A TROUGH NEAR THE WEST
COAST OF THE CONUS. DOWNSTREAM OF THIS TROUGH, MOST MODELS PREDICT A RIDGE OVER
THE CENTRAL CONUS AND FLAT FLOW OVER THE EASTERN CONUS. THE DETERMINISTIC GFS
SOLUTIONS SHOW A MORE DISTINCT SPLIT FLOW AND A MORE AMPLIFIED PATTERN RELATIVE
TO THE ENSEMBLE MEANS CHARACTERIZED BY TROUGHS OVER THE WESTERN CONUS AND OFF
THE EAST COAST AND A RIDGE OVER THE CENTRAL CONUS. HOWEVER, THERE ARE
SIGNIFICANT RUN TO RUN DIFFERENCES AMONG THE DETERMINISTIC GFS ON THE DETAILS
OF THESE FEATURES. OVER ALASKA, THE MODELS GENERALLY PREDICT A TROUGH OVER THE
BERING SEA EXTENDING SOUTHEASTWARD OVER THE GULF OF ALASKA. TODAY`S WEEK TWO
MANUAL 500-HPA HEIGHT BLEND IS WEIGHTED MOST HEAVILY TOWARD THE ENSEMBLE MEAN
SOLUTIONS FROM THE ECMWF.

PROBABILITIES OF ABOVE-NORMAL TEMPERATURES ARE ENHANCED FOR MUCH OF THE ROCKIES
AND CENTRAL AND SOUTHERN PLAINS DOWNSTREAM OF A TROUGH FORECAST NEAR THE WEST
COAST. ABOVE-NORMAL TEMPERATURES ARE SLIGHTLY FAVORED FOR PARTS OF THE
SOUTHEASTERN CONUS UNDERNEATH PREDICTED WEAKLY POSITIVE 500-HPA HEIGHT
ANOMALIES AND LOW AMPLITUDE FLOW. CONVERSELY, BELOW-NORMAL TEMPERATURES ARE
FAVORED FOR PARTS OF THE GREAT LAKES AND NORTHEAST IN ASSOCIATION WITH A TROUGH
PREDICTED OVER EASTERN CANADA. BELOW-NORMAL TEMPERATURES ARE ALSO FAVORED FOR
MUCH OF THE WEST COAST IN ASSOCIATION WITH A FORECAST TROUGH. ABOVE-NORMAL
TEMPERATURES ARE SLIGHTLY FAVORED FOR PARTS OF NORTHWESTERN ALASKA CONSISTENT
WITH GEFS REFORECAST GUIDANCE.

ENHANCED PROBABILITIES OF ABOVE-MEDIAN PRECIPITATION ARE INDICATED FOR MUCH OF
THE WEST RELATED TO A TROUGH PREDICTED NEAR THE WEST COAST. ABOVE-MEDIAN
PRECIPITATION IS SLIGHTLY FAVORED FROM PARTS OF THE SOUTHERN PLAINS EXTENDING
NORTHEASTWARD TO THE MID-ATLANTIC DUE TO THE POTENTIAL FOR SHORTWAVE TROUGHS TO
AFFECT THESE REGIONS. THERE ARE ENHANCED PROBABILITIES OF ABOVE-MEDIAN
PRECIPITATION FOR THE ALASKA PANHANDLE RELATED TO A TROUGH FORECAST OFF THE
COAST. NEAR TO BELOW-MEDIAN PRECIPITATION IS FAVORED FOR NORTHWESTERN ALASKA TO
THE NORTH OF THE EXPECTED MEAN STORM TRACK.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 5 PERCENT OF TODAY`S OPERATIONAL
0Z GFS CENTERED ON DAY 11...10 PERCENT OF TODAY`S 0Z GFS ENSEMBLE MEAN CENTERED
ON DAY 11...15 PERCENT OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...25
PERCENT OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11...20 PERCENT OF
TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11...20 PERCENT OF
YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10...AND 5 PERCENT OF
YESTERDAY`S 12Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 10.

FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO HIGH MODEL SPREAD.

FORECASTER: SCOTT HANDEL

NOTES:


AUTOMATED FORECASTS ARE ISSUED ON SATURDAY AND SUNDAY. OCCASIONALLY MANUAL
INTERVENTION IS NECESSARY TO ADDRESS QUALITY CONTROL AND CONSISTENCY ISSUES.
IN THESE CASES, FORECASTS ARE MANUALLY DRAWN BUT A FULL DISCUSSION IS NOT
ISSUED.

THE NOTATION FOR THE CATEGORICAL FORECAST INDICATED ON THE MAPS IS
THE SAME AS THAT IN THE TABLES: A-ABOVE   N-NEAR NORMAL   B-BELOW

THE TEMPERATURE MAP SHOWS REGIONS WITH > 33% CHANCE OF BEING WARMER
(ORANGE, "A"), COLDER (BLUE, "B"), OR CLOSE TO (UNSHADED, "N")
HISTORICAL AVERAGE VALUES FOR THE CALENDAR PERIOD OF THE FORECAST
(DASHES, "F").  LABELS ON THE SHADED LINES GIVE THE PROBABILITY
(> 33%) OF THE MORE LIKELY CATEGORY (B OR A).  PROBABILITY OF N IS
ALWAYS < 40%.

THE PRECIPITATION MAP SHOWS REGIONS WITH > 33% CHANCE OF BEING
WETTER (GREEN, "A"), DRIER (TAN, "B"), OR CLOSE TO (UNSHADED, "N")
HISTORICAL MEDIAN VALUES FOR THE CALENDAR PERIOD OF THE FORECAST
(DASHES, "INCHES").  LABELS ON THE SHADED LINES GIVE THE PROBABILITY
(> 33%) OF THE MORE LIKELY CATEGORY (B OR A).  PROBABILITY OF N IS
ALWAYS < 40%.

IN THE SOUTHWEST AND OTHER CLIMATOLOGICALLY DRY REGIONS - THERE WILL
BE A GREATER THAN 33.3% CHANCE OF NO PRECIPITATION AND OCCASIONALLY
EVEN A NORMAL (I.E. MEDIAN) VALUE OF ZERO - ESPECIALLY DURING THE DRY
SEASONS.  IN SUCH CASES A FORECAST OF NEAR NORMAL IS EFFECTIVELY A
FORECAST OF LITTLE OR NO PRECIPITATION.

THE CLIMATE PREDICTION CENTER USES 1981-2010 BASE PERIOD MEANS FOR
TEMPERATURE...PRECIPITATION...AND 500-HPA HEIGHTS AS REFERENCE IN
THE CLIMATE OUTLOOKS.

THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON MAY
15

ANALOGS TO THE 5 DAY MEAN OBSERVED PATTERN CENTERED 3 DAYS AGO (D-3)
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE
INCLUDE THE 5 DAY PERIODS CENTERED ON THE FOLLOWING DATES:
19940405 - 20040421 - 19930427 - 19940429 - 19690416


ANALOGS TO THE 7 DAY MEAN OBSERVED PATTERN CENTERED 4 DAYS AGO (D-4)
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE
INCLUDE THE 7 DAY PERIODS CENTERED ON THE FOLLOWING DATES:
19930427 - 19940430 - 19690415 - 19940404 - 20040421


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 24 - 28 2014

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  N    A     OREGON      N    A     NRN CALIF   N    A
SRN CALIF   B    A     IDAHO       N    A     NEVADA      N    A
W MONTANA   N    A     E MONTANA   N    A     WYOMING     N    N
UTAH        N    N     ARIZONA     N    N     COLORADO    A    B
NEW MEXICO  A    N     N DAKOTA    B    A     S DAKOTA    N    A
NEBRASKA    A    N     KANSAS      A    N     OKLAHOMA    A    N
N TEXAS     A    N     S TEXAS     A    N     W TEXAS     A    N
MINNESOTA   B    A     IOWA        N    A     MISSOURI    A    A
ARKANSAS    A    A     LOUISIANA   A    N     WISCONSIN   B    A
ILLINOIS    A    A     MISSISSIPPI A    N     MICHIGAN    B    A
INDIANA     N    A     OHIO        N    A     KENTUCKY    A    A
TENNESSEE   A    A     ALABAMA     A    N     NEW YORK    B    A
VERMONT     B    A     NEW HAMP    B    A     MAINE       B    A
MASS        B    A     CONN        B    A     RHODE IS    B    A
PENN        N    A     NEW JERSEY  B    A     W VIRGINIA  N    A
MARYLAND    N    A     DELAWARE    N    A     VIRGINIA    N    N
N CAROLINA  N    N     S CAROLINA  A    N     GEORGIA     A    N
FL PNHDL    A    B     FL PENIN    A    B     AK N SLOPE  A    N
AK ALEUTIAN N    N     AK WESTERN  A    B     AK INT BSN  A    B
AK S INT    N    N     AK SO COAST N    N     AK PNHDL    N    N



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR APR 26 - MAY 02, 2014

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  N    A     OREGON      B    A     NRN CALIF   B    A
SRN CALIF   B    A     IDAHO       A    A     NEVADA      N    A
W MONTANA   A    A     E MONTANA   A    A     WYOMING     A    A
UTAH        A    A     ARIZONA     N    N     COLORADO    A    N
NEW MEXICO  A    N     N DAKOTA    N    A     S DAKOTA    A    A
NEBRASKA    A    N     KANSAS      A    N     OKLAHOMA    A    N
N TEXAS     A    A     S TEXAS     A    N     W TEXAS     A    N
MINNESOTA   B    N     IOWA        N    N     MISSOURI    A    N
ARKANSAS    A    A     LOUISIANA   N    N     WISCONSIN   B    N
ILLINOIS    N    N     MISSISSIPPI A    A     MICHIGAN    B    N
INDIANA     B    A     OHIO        B    A     KENTUCKY    A    A
TENNESSEE   A    A     ALABAMA     A    N     NEW YORK    B    A
VERMONT     B    N     NEW HAMP    B    N     MAINE       B    N
MASS        B    N     CONN        B    A     RHODE IS    B    N
PENN        N    A     NEW JERSEY  B    A     W VIRGINIA  N    A
MARYLAND    N    A     DELAWARE    N    A     VIRGINIA    N    A
N CAROLINA  N    A     S CAROLINA  N    N     GEORGIA     A    N
FL PNHDL    N    B     FL PENIN    N    B     AK N SLOPE  A    N
AK ALEUTIAN N    N     AK WESTERN  A    B     AK INT BSN  N    N
AK S INT    N    N     AK SO COAST N    N     AK PNHDL    N    A

                           LEGEND
TEMPS WITH RESPECT TO NORMAL     PCPN WITH RESPECT TO MEDIAN
A - ABOVE   N  - NEAR NORMAL     A - ABOVE   N - NEAR MEDIAN
B - BELOW                        B - BELOW

THE FORECAST CLASSES REPRESENT AVERAGES FOR EACH STATE. NORMAL
VALUES - WHICH MAY VARY WIDELY ACROSS SOME STATES - ARE
AVAILABLE FROM YOUR LOCAL WEATHER SERVICE FORECAST OFFICE.

FOR ADDITIONAL INFORMATION SEE MESSAGE FXUS06 KWBC - ON AWIPS AS
PMDMRD.

$$



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